Mexico outraged at U.S. surveillance of ally Felipe Calderon

It's not enough that the United States spied on Mexico, but new documents released from former U.S. intelligence contractor Edward Snowden reveal that America targeted its touted friend and ally, former President Felipe Calderon, and placed him under surveillance.

The German magazine Der Spiegel made the charges in a weekend story, citing Mr. Snowden's documents from the National Security Agency. One NSA document read that the United States monitored a range of "diplomatic, economic and leadership communications" to gauge the "internal stability" on the country. But the documents also revealed that U.S. authorities tapped into an email server that was used by Mr. Calderon and members of his cabinet, the Los Angeles Times reported.

The revelation outraged many in the nation who saw the United States as having a close relationship with the former conservative president.

The report also maintains that the NSA spied on Enrique Pena Nieto, the current president, while he was campaigning for office, the Los Angeles Times said.

A spokesman for the American Embassy in Mexico declined to comment on the spy claims. But diplomatic officials did release a statement:" As a matter of policy, we have made clear that the United States gathers foreign intelligence of the type gathered by all nations."

Meanwhile, the Obama administration has promised to investigate, the Los Angeles Times reported.

Mexico's Foreign Ministry demanded a quick conclusion to the investigation, saying that the spying was "unacceptable, unlawful and contrary to Mexican law and international law," the Los Angeles Times reported.